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Q wave in paediatric myocarditis: an underinvestigated, readily available prognostic factor
Hamid Mohammadi1, Reza Fereidooni2, Nima Mehdizadegan1
1Department of Pediatrics, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
Insights
Pathological Q waves on electrocardiograms (ECG) indicate severe acute myocarditis (AM) in children. This finding is associated with increased complications, longer hospital stays, and poorer outcomes, necessitating close monitoring and intensive treatment.
Area of Science:
- Pediatric Cardiology
- Electrophysiology
- Critical Care Medicine
Background:
- Myocarditis is a serious, potentially fatal condition in children.
- Pathological Q waves on ECGs can signify permanent heart damage in various cardiac diseases.
- The prognostic significance of Q waves in pediatric acute myocarditis (AM) is not well-established.
Purpose of the Study:
- To investigate the clinical significance and prognostic value of pathological Q waves in children diagnosed with acute myocarditis (AM).
- To compare the characteristics and outcomes of pediatric AM patients with and without Q wave findings on ECG.
Main Methods:
- Retrospective observational study of 59 pediatric patients with AM.
- Classification of patients into Q wave and non-Q wave myocarditis groups based on ECG findings.
- Analysis of laboratory data, echocardiography, treatment protocols, and hospital outcomes.
Main Results:
- Pathological Q waves were present in 52.5% of pediatric AM patients.
- The Q wave group exhibited higher troponin I levels and longer hospitalizations.
- Q wave patients required more intensive treatments, including mechanical ventilation, and had worse outcomes, including mortality and reduced LVEF.
Conclusions:
- Pathological Q waves in pediatric AM are associated with more severe disease and poorer prognoses.
- ECG Q wave findings serve as a crucial indicator for close monitoring and intensive management in AM.
- Further research is needed to validate the prognostic accuracy of Q waves in AM and guide treatment strategies.
Background:
Myocarditis is an uncommon disease in children with potentially fatal consequences. An electrocardiogram (ECG) change seen in myocarditis is pathological Q wave. Pathological Q wave is linked to permanent damage and myocardial death in several cardiac diseases. We investigated the significance of pathological Q waves in children with acute myocarditis (AM).
Methods:
This retrospective observational study analysed the data of 59 children with AM admitted to our hospital between January 2016 and July 2021. They were divided into Q wave and non-Q wave myocarditis groups. Patients' laboratory data, echocardiography, treatment and hospital outcome were analysed.
Results:
Patients were 64.4% male and had a median age of 6 years and 9 months. Pathological Q waves were found in 52.5% of the patients. Q wave myocarditis group had higher troponin I values (499 vs. 145 ng/L, p = 0.011) and longer hospital stays (13 vs. 9 days, p = 0.020) than the non-Q wave group. They also required higher doses of inotropic or vasoactive drugs. 61.3% of Q wave patients needed mechanical ventilation compared to 35.7% of non-Q wave patients (p = 0.069). All the patients who died or discharged with an LVEF < 30% belonged to the Q wave group.
Conclusion:
Q wave in AM warrants close monitoring and intensive treatment as it accompanies more severe complications and poorer outcomes. This readily available ECG finding can be a clue to prognoses of AM patients. Further research with larger populations is needed to better understand Q wave prognostic accuracy and its potential role in guiding more expensive treatments.
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